Dive in with the world's largest freshwater fishes on a special "megafish" episode. Our guest is Zeb Hogan: big fish enthusiast, researcher, author, host of National Geographic's Monster Fish, and director of Wonders of the Mekong Project. From American Paddlefish to Mekong Giant Catfish, we cover the array of freshwater fishes that reach lengths over six feet or weigh more than 200 pounds.